package com.hmdp.service.impl;

import cn.hutool.core.bean.BeanUtil;
import com.hmdp.dto.Result;
import com.hmdp.entity.VoucherOrder;
import com.hmdp.mapper.VoucherOrderMapper;
import com.hmdp.service.ISeckillVoucherService;
import com.hmdp.service.IVoucherOrderService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.utils.RedisWorker;
import com.hmdp.utils.UserHolder;
import lombok.CustomLog;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.redisson.api.RLock;
import org.redisson.api.RedissonClient;
import org.springframework.aop.framework.AopContext;
import org.springframework.context.annotation.Bean;
import org.springframework.core.io.ClassPathResource;
import org.springframework.data.redis.connection.stream.*;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.script.DefaultRedisScript;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import javax.annotation.PostConstruct;
import java.time.Duration;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.concurrent.*;

/**
 * <p>
 *  服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */

@Slf4j
@RequiredArgsConstructor
@Service
public class VoucherOrderServiceImpl extends ServiceImpl<VoucherOrderMapper, VoucherOrder> implements IVoucherOrderService {

    private final ISeckillVoucherService seckillVoucherService;

    private final RedisWorker redisWorker;

    private final StringRedisTemplate redisTemplate;

    private final RedissonClient redissonClient;

    //private BlockingQueue<VoucherOrder> orderTasks = new ArrayBlockingQueue<>(1024*1024);

    private static final ExecutorService EXECUTORSERVICE = Executors.newSingleThreadExecutor();

    @PostConstruct
    private void init(){
        EXECUTORSERVICE.submit(new VoucherOrderHandler());
    }

    private class VoucherOrderHandler implements Runnable{

        @Override
        public void run() {
            while (true){
                try {
                    //1 获取队列中的订单信息
                    //VoucherOrder voucherOrder = orderTasks.take();
                    List<MapRecord<String, Object, Object>> list = redisTemplate.opsForStream().read(
                            Consumer.from("g1", "c1"),
                            StreamReadOptions.empty().count(1).block(Duration.ofSeconds(2)),
                            StreamOffset.create("stream.orders", ReadOffset.lastConsumed())
                    );
                    //判断消息是否获取成功
                    if(list == null || list.isEmpty()){
                        continue;
                    }
                    //解析队列中的订单

                    MapRecord<String, Object, Object> record = list.get(0);
                    Map<Object, Object> values = record.getValue();
                    VoucherOrder voucherOrder = BeanUtil.fillBeanWithMap(values, new VoucherOrder(), true);
                    //2 创建订单
                    handleVoucherOrder(voucherOrder);
                    //ack确认 SACK streams.order g1 id
                    redisTemplate.opsForStream().acknowledge("stream.orders","g1",record.getId());
                } catch (Exception e) {
                    log.error("处理订单异常",e);
                    handlePendingList();
                }

            }
        }
        private void handlePendingList() {
            while (true) {
                try {
                    //1 获取pendinglist
                    List<MapRecord<String, Object, Object>> list = redisTemplate.opsForStream().read(
                            Consumer.from("g1", "c1"),
                            StreamReadOptions.empty().count(1),
                            StreamOffset.create("stream.orders", ReadOffset.from("0"))
                    );
                    //判断消息是否获取成功
                    if (list == null || list.isEmpty()) {
                        break;
                    }
                    //解析队列中的订单

                    MapRecord<String, Object, Object> record = list.get(0);
                    Map<Object, Object> values = record.getValue();
                    VoucherOrder voucherOrder = BeanUtil.fillBeanWithMap(values, new VoucherOrder(), true);
                    //2 创建订单
                    handleVoucherOrder(voucherOrder);
                    //ack确认 SACK streams.order g1 id
                    redisTemplate.opsForStream().acknowledge("stream.orders", "g1", record.getId());
                } catch (Exception e) {
                    log.error("处理pendinglist订单异常", e);
                }
            }
        }
    }



    private void handleVoucherOrder(VoucherOrder voucherOrder) {

        Long userId = voucherOrder.getUserId();
        RLock lock = redissonClient.getLock("lock:order:" + userId);

        boolean isLock = lock.tryLock();
        if (!isLock) {
            log.error("不允许重复下单");
            return;
        }
        //获取代理对象
        try {
            proxy.createVoucherOrder(voucherOrder);
        } finally {
            lock.unlock();
        }
    }

    private static final DefaultRedisScript<Long> SECKILL_SCRIPT;
    static {
        SECKILL_SCRIPT = new DefaultRedisScript<>();
        SECKILL_SCRIPT.setLocation(new ClassPathResource("seckill.lua"));
        SECKILL_SCRIPT.setResultType(Long.class);
    }
    private IVoucherOrderService proxy;


    @Override
    public Result seckillVoucher(Long voucherId) {
        Long userId = UserHolder.getUser().getId();
        long orderId = redisWorker.nextId("order");
        //1.执行lua脚本
        Long result = redisTemplate.execute(SECKILL_SCRIPT,
                Collections.emptyList(),
                voucherId.toString(),
                userId.toString(),
                String.valueOf(orderId)
        );

        result.intValue();
        //2.1.不为0，代表没有购买资格
        if (result != 0) {
            return Result.fail(result==1? "库存不足":"不能重复下单");
        }
//        // 2.2.为0，有购买资格，把下单信息保存到阻塞队列
//
//        VoucherOrder voucherOrder = new VoucherOrder();
//        voucherOrder.setId(orderId);
//        voucherOrder.setUserId(userId);
//        voucherOrder.setVoucherId(voucherId);
//        orderTasks.add(voucherOrder);

        proxy = (IVoucherOrderService) AopContext.currentProxy();
        // 3.返回订单id
        return Result.ok(orderId);




        /*//查询优惠券
        SeckillVoucher voucher = seckillVoucherService.getById(voucherId);
        //秒杀是否开始
        if (voucher.getBeginTime().isAfter(LocalDateTime.now())) {
            return Result.fail("秒杀未开始");
        }
        //秒杀是否结束
        if (voucher.getEndTime().isBefore(LocalDateTime.now())) {
            return Result.fail("秒杀已经结束");
        }
        //库存是否充足
        if (voucher.getStock()<1) {
            return Result.fail("库存不足");
        }
        Long userId = UserHolder.getUser().getId();

        //创建锁对象
        //SimpleRedisLock lock = new SimpleRedisLock("order:" + userId, redisTemplate);

        RLock lock = redissonClient.getLock("lock:order:"+userId);

        boolean isLock = lock.tryLock();
        if (!isLock) {
            return Result.fail("一人只让下一单");
        }
        //获取代理对象
        try {
            IVoucherOrderService proxy = (IVoucherOrderService) AopContext.currentProxy();
            return proxy.createVoucherOrder(voucherId);
        } finally {
            lock.unlock();
        }*/
    }


    @Transactional
    public Result createVoucherOrder(VoucherOrder voucherOrder) {
        //一人一单
        Long userId = voucherOrder.getUserId();
//        Long userId = UserHolder.getUser().getId();
        //查询订单
        int count = query().eq("user_id", userId)
                .eq("voucher_id", voucherOrder.getVoucherId())
                .count();
        if (count > 0) {
            //用户购买过了
            return Result.fail("用户购买过了");
        }

        //扣减库存
        boolean success = seckillVoucherService.update()
                .setSql("stock = stock -1 ")
                .eq("voucher_id", voucherOrder.getVoucherId())
                .gt("stock", 0)
                .update();
        if (!success) {
            return Result.fail("库存不足");
        }

        /*//创建订单
        *//*VoucherOrder voucherOrder = new VoucherOrder();
        long orderId = redisWorker.nextId("order");
        voucherOrder.setId(orderId);
        voucherOrder.setUserId(userId);
        voucherOrder.setVoucherId(voucherId);*/
        save(voucherOrder);

        //返回商品id
        return Result.ok();

    }
}

